The overall objective of the proposed research is to develop an understanding of the biomechanical function of the temporomandibular joint (TMJ) by determining the mechanical properties of the soft tissue components in the TMJ (i.e., meniscus, condylar cartilage, fibrous tissue of the fossa). A primary goal of this research is to develop mechanical models of the soft tissue of the TMJ by the application of existing theoretical models to experimental data obtained from the soft tissue. Soft tissue from human, porcine, and bovine TM joints will be procured. Testing includes consolidation and stress relaxation, along with the determination of osmotic swelling pressure, proteoglycan content, and permeability of these tissues. A theoretical model developed for soil consolidation will be used to fit the experimental data from consolidation and stress relaxation tests and permeability coefficients of the tissue will be determined. Knowledge of the mechanical properties of the tissues, will lead to an understanding of the function of the TMJ in normal and pathologic joints. In addition, porous and non-porous TMJ reconstructive biomaterials will be tested in the same manner as the soft tissue from the temporomandibular joint, and the results will be compared between the two to assess how closely the functioning of the man-made materials correspond to those that they replace.